Security is reductionist. Once your system is broken it doesn't matter how or where, it just is. If you need SSL, you must use it. You cannot hack around it, since the attacker will simply MITM you without it, or find a side channel to load the malicious code and then use one of the dozens of flexibilities in the JS runtime to get your sensitive info.

The opposite is also true: if your SSL setup is compromised (e.g. Leaked private key), client side crypto does nothing to protect you since the attacker can just MITM your crypto code inside the runtime, get data out of the DOM, etc.

There are no cases left where client side crypto provides any additional security. Some future server-browser model might change that, but not anything that exists on the web currently.